There is significant variation in the type and amount of taxes that residents of developed countries must pay, even within the member nations of the Organization for Economic Cooperation and Development (OECD).

The basic principles of taxation are nearly as old as human society—the history of taxes stretches thousands of years into the past. Taxation evolved significantly as empires expanded and civilizations become more structured.

Personal income tax is one of the oldest forms of taxation. Practically every national and provincial government levies taxes on the income of citizens and businesses that generate money within its borders.